Telephone-transmitter



(No Model.)

F. DU PONT MARSTON.

TELEPHONE TRANSMITTER.

No. 329,327; Patented Oct. 27, 1885. i'zg'kl.

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BY i y ATTORNEY u. PETERS, Pmto-Lnho npher. Wallunginn. D. c

UNITED STATES PATENT OFFICE.

F. DU PONT MARSTON, OF PHILADELPHIA, PENNSYLVANIA.

TELEPHONE-TRANSMITTER.

SPECIFICATION forming part of Letters Patent No. 329,327, dated October 27, 1885.

Application filed Ma 1, 1885. Serial No. 164,735. (No model.)

To all whom it may concern:

Be it known that I, F. DU Pour MAnsrroN, a citizen of the United States, residing in the city and county of Philadelphia, State of Pennsylvania, have invented a new and useful Improvement in Telephonic Transmitters, which improvement is fully set forth in the following specification and accompanying drawings, in which- Figure 1 represents aview of the interior of an electric transmitter embodying my inven tion. Fig. 2 represents a vertical section of the transmitter in line a: 00, Fig. 1. Fig. 3 represents a longitudinal section thereof in line 3 I Fig. 1.

similar letters of reference indicate corresponding parts in the several figures.

My invention relates to improvements in telephonic transmitters; and it consists of means. substantially as hereinafter set forth, whereby an increased delicacy of operation is effected and a uniformity, fullness, sharpness, and distinctness are attained in the trans mission of articulate speech.

Referring to the drawings, A represents a diaphragm, the same consisting of a disk of glass, which is properly secured to the divisional plate or table A within the box or casing of the transmitter, and carrying on its center a holder, B, for a piece of carbon or electrode, 0, said holder resting freely on the diaphragm A, and held in position thereon by means of a spring or springs, D, attached to the plate A, said diaphragm being supported loosely on an annular pad or cushion of felt or other suitable material, E, which latter is secured to the plate A, it being noticed that the diaphragm is arranged horizontally on said plate.

F represents ablock of carbon or electrode, arranged vertically and passing freely through a boss or guide, G, supported above the plate A, the lower end of said electrode resting freely against the electrode 0. In the plate A is an opening, H, the same thus being on the under side of the diaphragm A, at the center thereof, and communicating with atube or passage, J ,which is secured to the plate A, and communicates with the mouth-piece of the instrument.

It will be seen that by the employment of glass as the material for a diaphragm in telephone-transmitters, and the support of the same 011 the pad or cushion of flexible material, the diaphragm is caused to vibrate, and the vibrations are transmitted to the electrodes, so that the sound is conveyed full and distinct. The upper electrode is adjustable in length or thickness, so as to obtain the required weight, whereby the vibrations of the diaphragm are uniforni,aud when the adjustment is obtained the same is permanent. The electrodes are properly connected with an induction-coil and battery in any suitable manner. In the present case a band or ring encircles the upper electrode, and to said band or ring is connected a wire-leading to the inductioncoil. The wire of the lower electrode is connected with the springs D, or may be attached directly to the said electrode or the holder thereof, and is likewise connected with the battery.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-- 1. In a telephonictransmitter, theglass diaphragm A, suitably supported on the annular pad E, in combination with the holder B, resting on said diaphragm, electrode 0, and spring D, substantially as described.

2. In atelephonictransmitter,thediaphragm A, resting on the annular pad E, in combination with the plate A, having opening H, tube J, and spring D, substantially as and for the purpose set forth.

3. The diaphragm A, resting on the pad E, in combination with plate A, having opening H, tube J, spring D, holder B,supported on the diaphragm A,carbon or electrode G,supported on the holder B, electrode F, and annular guide G, the said electrodes being suitably connected to an induction-coil and battery, substantially as described.

F. DU PONT MARSTON.

WVitnesses:

J OHN A. WIEDERSHEIM, A. 1?. GRANT. 

